JP3842398B2 - Joint structure of manhole and connecting pipe - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a joint structure when connecting a connecting pipe to a side wall of a manhole, and more particularly, to a joint structure that has great flexibility in a joint portion without damaging the connecting pipe.
[0002]
[Prior art]
A conventional joint structure of this type is disclosed in, for example, Japanese Patent Application Laid-Open No. 8-41920.
[0003]
As shown in FIG. 5 , the rigid socket b having an inner diameter sufficiently larger than the outer diameter of the attachment pipe (connection pipe) a is fixed around the attachment hole d on the side wall of the manhole c, and the socket b The base of the tapered flexible cylindrical body e whose inner diameter is substantially equal to the outer diameter of the mounting tube a is fixed to the mounting hole d of the manhole c, the rigid socket b, and the flexible cylindrical body e. By inserting the tube a, it is configured to support it at the tip of the flexible tube e.
[0004]
[Problems to be solved by the invention]
In the conventional joint structure described above, the base end of the mounting tube a is inserted to the position where it is substantially aligned with the inner peripheral surface through the mounting hole d of the manhole c. When the load acts and bends, the outer peripheral edge of the proximal end of the mounting tube a comes into contact with the inner peripheral surface of the mounting hole d, or comes into contact with the outer peripheral surface of the invert (water conduit) f inserted into the manhole c. .
[0005]
In this case, not only is the base end portion of the attachment tube a damaged, but sufficient flexibility cannot be obtained.
[0006]
In order to solve this problem, it is conceivable to increase the inner diameter of the mounting hole d and provide a large gap g between the outer peripheral surface of the mounting tube a. However, if it does in this way, the intensity | strength of the manhole c will be affected or the quantity which the foreign material contained in the fluid will accumulate in the clearance gap g will increase, and this will also anticipate that flexibility is inhibited.
[0007]
In the conventional joint structure described above, the mounting hole d and the gap g between the rigid socket b and the mounting tube a may be filled with mortar or the like. Therefore, the earthquake resistance and flexibility are almost lost.
[0008]
The present invention has been made in order to solve the above-mentioned problems, and is a joint between a manhole and a connecting pipe that is highly flexible and can prevent the connecting pipe from being damaged by contact with the manhole or the like. Its purpose is to provide a structure.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the joint structure of the present invention is a joint structure for connecting a connection pipe for circulating a fluid in a manhole so that it can communicate with an attachment hole drilled in a side wall of the manhole,
A joint pipe having a large diameter portion larger than the outer diameter of the connection pipe and larger than the mounting hole and a small diameter section smaller than the outer diameter of the connection pipe; and a small diameter of the joint pipe The fixing portion is secured to the outer peripheral wall of the manhole around the mounting hole while maintaining watertightness, and the base end portion of the connection pipe is sealed in the gap between the large diameter portion of the joint pipe. And at least the opening end near the bottom of the gap formed between the outer peripheral surface of the connection pipe and the inner peripheral surface of the joint pipe is expanded or contracted. It is characterized by being closed by a flexible closing member .
[0010]
It is preferable to provide a guide tube portion that can be inserted into the mounting hole of the manhole at the base end portion of the joint pipe.
[0012]
According to the present invention, a joint pipe having a diameter larger than the outer diameter of the connection pipe is fixed to the outer peripheral wall of the manhole, and the connection pipe is loosely inserted into the joint pipe. Therefore, the pipe diameter of the joint pipe is appropriately designed. Thus, a large bending space can be formed in the joint pipe, and the flexibility of the connection pipe can be increased.
[0013]
Further, since the connecting pipe is not inserted into the manhole as in the prior art, the connecting pipe does not come into contact with the manhole or the like.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0015]
FIG. 1 shows a plan view of a first embodiment of the present invention, and a mounting hole 2 is provided through a side wall of the manhole 1 near the bottom.
[0016]
In the mounting hole 2, a guide tube portion 3 b provided continuously to the proximal end portion of the small diameter portion 3 a in the iron joint pipe 3 is loosely inserted to a position substantially aligned with the inner peripheral surface of the manhole 1. A gap formed between the inner surface of the guide cylinder 3 and the outer peripheral surface of the guide tube portion 3 b is sealed by inserting an O-ring 4.
[0017]
A circular and curved mounting plate 5 is continuously provided on the outer peripheral surface of the small-diameter portion 3a. The mounting plate 5 is formed by screwing bolts 7 into a plurality of female screw anchors 6 embedded in the outer peripheral wall of the manhole 1. Thus, the manhole 1 is fixed. The inner diameter of the small diameter portion 3a is slightly smaller than the outer diameter of the connecting pipe 8 described later so that the connecting pipe 8 is not inserted into the small diameter portion 3a.
[0018]
In the large-diameter portion 3c of the joint pipe 3, the base end portion of the connecting pipe 8 in which the inner and outer peripheral surfaces of the concrete pipe body are covered with fiber reinforced plastic (FRP) is approximately half as long as the large-diameter portion 3c. It is inserted loosely. The tube diameter of the large diameter portion 3 c is sufficiently larger than the outer diameter of the connection tube 8, and an inward annular piece whose inner peripheral edge is close to the outer peripheral surface of the connection tube 8 is at the open end of the large diameter portion 3 c. 3d is continuously provided.
[0019]
A rubber seal ring 10 is fitted in an annular groove 9 formed on the inner peripheral surface of the opening end of the large diameter portion 3 c, and the inner peripheral surface is pressed against the outer peripheral surface of the connection pipe 8. Watertightness is maintained.
[0020]
In the first embodiment, when a bending load is applied to the connecting pipe 8 due to an earthquake or the like, the connecting pipe 8 can be bent by the gap in the large diameter portion 3c. Since the connecting pipe 8 is not inserted into the mounting hole 2 of the manhole 1 as in the prior art, the amount of bending at this time can be increased regardless of the diameter of the mounting hole 2.
[0021]
That is, since the design of the diameter of the large diameter portion 3c can be freely changed according to the outer diameter of the connecting pipe 8, a large bending space can be formed in the large diameter portion 3c. Therefore, unlike the conventional one, there is no possibility that the base end portion of the connecting pipe 8 abuts on the mounting hole 2 of the manhole 1 or the invert 11 inserted into the manhole 1 to be damaged.
[0022]
The size of the mounting hole 2 of the manhole 1 may be a minimum hole diameter that ensures a required flow rate, and does not affect the strength of the manhole 1.
[0023]
FIG. 2 shows a second embodiment of the present invention. In this embodiment, the clearance S between the inner peripheral surface of the large-diameter portion 3 c and the outer peripheral surface of the proximal end portion of the connecting pipe 8 in the joint pipe 3 is shown. It is blocked by inserting a filler 12 having elasticity such as urethane sponge.
[0024]
If it does in this way, it can prevent that the foreign substance contained in the fluid enters and accumulates in the clearance gap S, and the flexibility of the connection pipe 8 is prevented.
[0025]
FIG. 3 shows a third embodiment of the present invention. In this embodiment, a bellows-like seal member 13 extending toward the manhole 1 side is fixed to the outer peripheral surface of the proximal end portion of the connection pipe 8, The opening of the gap S is closed by pressing the tip of the joint with the step portion between the small diameter portion 3 a and the large diameter portion 3 c of the joint pipe 3.
[0026]
Also in this embodiment, it is possible to prevent the accumulation of impurities in the gap S, so that the flexibility of the connecting pipe 8 is not hindered. In addition, since impurities contained in the fluid are likely to accumulate near the tube bottom, the closing member such as the filler 12 and the seal member 13 as described above may be provided only near the tube bottom. .
[0027]
The present invention is not limited to the above embodiments.
[0028]
For example, the guide tube portion 3 b in the joint pipe 3 may be omitted so as not to be inserted into the mounting hole 2 of the manhole 1, and the mounting plate 5 may be directly mounted on the peripheral wall of the manhole 1 while maintaining water tightness.
[0029]
Further, the small diameter portion 3a may not be formed, and only the large diameter portion 3c having a larger diameter than the connection pipe 8 may be provided.
[0030]
Note that the method of fixing the seal ring 10 to the joint pipe 3 is not limited to the above-described embodiment, and the seal ring 10 is sandwiched between the flange 3e and the retaining ring 14 as shown in FIG. A structure in which the bolt 15 is fastened may be used. In particular, according to this configuration, the bolts 15 are tightened after the connection pipe 8 is inserted into the joint pipe 3 so that the pipes can be easily connected.
[0031]
【The invention's effect】
According to the present invention, since the connecting pipe is inserted into the joint pipe without being inserted into the manhole, a large bending space can be formed in the joint pipe, and the flexibility of the connecting pipe can be increased. it can. In addition, since impurities are prevented from entering and accumulating in the gap between the connecting pipe and the joint pipe, the flexibility of the connecting pipe is not hindered.
[0032]
Further, since the connecting pipe is not inserted into the manhole, even if the connecting pipe is bent, it is not damaged.
[0033]
According to the invention of claim 2, the joint pipe can be easily positioned and fixed around the mounting hole of the manhole, and the workability is improved.
[0035]
[Brief description of the drawings]
FIG. 1 is a partially cutaway plan view showing a first embodiment of the present invention.
FIG. 2 is also a partially cutaway plan view showing a second embodiment.
FIG. 3 is also a partially cutaway plan view showing a third embodiment.
FIG. 4 is a local cross-sectional view showing another embodiment of the connection portion between the joint pipe and the connection pipe.
FIG. 5 is a partially cutaway plan view showing a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Manhole 2 Mounting hole 3 Joint pipe | tube 3a Small diameter part 3b Guide cylinder part 3c Large diameter part 3d Inward annular piece 3e Flange 4 O-ring 5 Mounting plate 6 Female thread anchor 7 Bolt 8 Connection pipe 9 Annular groove 10 Seal ring 11 Invert 12 Filler (Occlusion member)
13 Sealing member (blocking member)
14 Retaining ring 15 Bolt S Clearance

Claims (2)

A joint structure for connecting the connecting pipe for circulating the fluid in the manhole so that it can communicate with the mounting hole formed in the side wall of the manhole,
A joint pipe having a large diameter portion larger than the outer diameter of the connection pipe and larger than the mounting hole and a small diameter section smaller than the outer diameter of the connection pipe; and a small diameter of the joint pipe The fixing portion is secured to the outer peripheral wall of the manhole around the mounting hole while maintaining watertightness, and the base end portion of the connection pipe is sealed in the gap between the large diameter portion of the joint pipe. And at least the opening end near the bottom of the gap formed between the outer peripheral surface of the connection pipe and the inner peripheral surface of the joint pipe is expanded or contracted. A joint structure of a manhole and a connecting pipe, which is closed by a flexible closing member .   The joint structure of a manhole and a connecting pipe according to claim 1, wherein a guide tube portion that can be inserted into a manhole mounting hole is provided at a base end portion of the joint tube.

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